Calculations for shear stress in yield test – Brookfield DV-III Ultra Rheometer User Manual

Page 112

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Brookfield Engineering Laboratories, Inc.

Page 112

Manual No. M98-211-E0912

The shear stress measurement range for the three standard (or supplied) vane spindles at each spring

torque is as follows:

Table D-5

SPINDLE

MODEL CODE

ON DV-III ULTRA

SCREEN

TK

SHEAR STRESS

RANGE (Pa)

V-71

LV

.09373

0.047 - 0.47

V-72

LV

.09373

0.19 - 1.9

V-73

LV

.09373

0.94 - 9.4

V-71

RV

1

0.5 - 5

V-72

RV

1

2 - 20

V-73

RV

1

10 - 100

V-71

HB

8

4 - 40

V-72

HB

8

16 - 160

V-73

HB

8

80 - 800

V-71

5xHB

40

20 - 200

V-72

5xHB

40

80 - 800

V-73

5xHB

40

400 - 4000

Calculations for Shear Stress in Yield Test

The following equations can be used to calculate the shear stress values after each packet of data

is obtained from the DV-III Ultra.

TK

x

YMC

x

T

10

τ

=

Where:

τ

= Yield Stress

(Pascals)

TK

= Model Torque Constant from Table D-2

YMC

= Yield Multiplier Constant from Table D-3

T

= % Torque reading

The following equations can be used to calculate the strain data after each packet of data is obtained

from the DV-III Ultra:

γ

=

θ

M

(S

x

T)

Where:

γ

= Strain

(rad)

θ

M

= Angular rotation of motor shaft

(rad)

S

= Radial Spring Factor

(rad/% torque)

T

= % Torque reading

(%)

=

ω

x

t

x

θ

M

2 π

60

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